Author: Peter Karl Baumann
Publisher:
ISBN:
Category :
Languages : en
Pages : 308

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Book Description

Author: Jacob Van Der Weide
Publisher:
ISBN:
Category :
Languages : en
Pages : 362

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Book Description

Author: Isay L. Krainsky
Publisher:
ISBN:
Category : Auger effect
Languages : en
Pages : 28

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Book Description
This report presents the results of the secondary electron emission spectroscopy study of hydrogenated diamond surfaces for single crystals and chemical vapor-deposited polycrystalline films. One-electron calculations of Auger spectra of diamond surfaces having various hydrogen coverages are presented, the major features of the experimental spectra are explained, and a theoretical model for Auger spectra of hydrogenated diamond surfaces is proposed. An energy shift and a change in the line shape of the carbon core-valence-valence (KVV) Auger spectra were observed for diamond surfaces after exposure to an electron beam or by annealing at temperatures higher than 950°C. This change is related to the redistribution of the valence-band local density of states caused by hydrogen desorption from the surface. A strong negative electron affinity (NEA) effect, which appeared as a large, narrow peak in the low-energy portion of the spectrum of the secondary electron energy distribution, was also observed on the diamond surfaces. A fine structure in this peak, which was found for the first time, reflected the energy structure of the bottom of the conduction band. Further, the breakup of the bulk excitons at the surface during secondary electron emission was attributed to one of the features of this structure. The study demonstrated that the NEA type depends on the extent of hydrogen coverage of the diamond surface, changing from the true type for the completely hydrogenated surface to the effective type for the partially hydrogenated surface.

Author: Christos Bandis
Publisher:
ISBN:
Category : Diamonds
Languages : en
Pages : 318

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Book Description

Author: Lawrence S. Pan
Publisher: Springer Science & Business Media
ISBN: 1461522579
Category : Technology & Engineering
Languages : en
Pages : 482

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Book Description
The use of diamond for electronic applications is not a new idea. As early as the 1920's diamonds were considered for their use as photoconductive detectors. However limitations in size and control of properties naturally limited the use of diamond to a few specialty applications. With the development of diamond synthesis from the vapor phase has come a more serious interest in developing diamond-based electronic devices. A unique combination of extreme properties makes diamond partiCularly well suited for high speed, high power, and high temperature applications. Vapor phase deposition of diamond allows large area films to be deposited, whose properties can potentially be controlled. Since the process of diamond synthesis was first realized, great progress have been made in understanding the issues important for growing diamond and fabricating electronic devices. The quality of both intrinsic and doped diamond has improved greatly to the point that viable applications are being developed. Our understanding of the properties and limitations has also improved greatly. While a number of excellent references review the general properties of diamond, this volume summarizes the great deal of literature related only to electronic properties and applications of diamond. We concentrate only on diamond; related materials such as diamond-like carbon (DLC) and other wide bandgap semiconductors are not treated here. In the first chapter Profs. C. Y. Fong and B. M. Klein discuss the band structure of single-crystal diamond and its relation to electronic properties.

Author: Tianyin Sun
Publisher:
ISBN:
Category : Condensed matter
Languages : en
Pages : 141

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Book Description
In this dissertation, combined photo-induced and thermionic electron emission from low work function diamond films is studied through low energy electron spectroscopy analysis and other associated techniques. Nitrogen-doped, hydrogen-terminated diamond films prepared by the microwave plasma chemical vapor deposition method have been the most focused material. The theme of this research is represented by four interrelated issues. (1) An in-depth study describes combined photo-induced and thermionic emission from nitrogen-doped diamond films on molybdenum substrates, which were illuminated with visible light photons, and the electron emission spectra were recorded as a function of temperature. The diamond films displayed significant emissivity with a low work function of ~ 1.5 eV. The results indicate that these diamond emitters can be applied in combined solar and thermal energy conversion. (2) The nitrogen-doped diamond was further investigated to understand the physical mechanism and material-related properties that enable the combined electron emission. Through analysis of the spectroscopy, optical absorbance and photoelectron microscopy results from sample sets prepared with different configurations, it was deduced that the photo-induced electron generation involves both the ultra-nanocrystalline diamond and the interface between the diamond film and metal substrate. (3) Based on results from the first two studies, possible photon-enhanced thermionic emission was examined from nitrogen-doped diamond films deposited on silicon substrates, which could provide the basis for a novel approach for concentrated solar energy conversion. A significant increase of emission intensity was observed at elevated temperatures, which was analyzed using computer-based modeling and a combination of different emission mechanisms. (4) In addition, the electronic structure of vanadium-oxide-terminated diamond surfaces was studied through in-situ photoemission spectroscopy. Thin layers of vanadium were deposited on oxygen-terminated diamond surfaces which led to oxide formation. After thermal annealing, a negative electron affinity was found on boron-doped diamond, while a positive electron affinity was found on nitrogen-doped diamond. A model based on the barrier at the diamond-oxide interface was employed to analyze the results. Based on results of this dissertation, applications of diamond-based energy conversion devices for combined solar- and thermal energy conversion are proposed.

Author: Società italiana di fisica
Publisher: IOS Press
ISBN: 1614992207
Category : Science
Languages : en
Pages : 635

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Book Description
Diamond is an extreme material among possible atomic aggregations in nature, and as such has many extreme properties. This unique position makes it a fascinating subject both for science and for applications. This has been particularly true in recent years, since the surprising discovery at Union Carbide (1953) of the possibility of chemical vapour deposition of diamond films at low pressures, where diamond is metastable with respect to graphite. This discovery cleared the way to the development of economical deposition techniques that have been obtaining progressively better-quality diamond, both pure and doped, in a controlled way and for a variety of applications. The remarkable properties and applications range from mechanical (the extreme hardness, tensile and compressive strength, wear performance) to thermal (the highest conductivity), optical (wide range of transparency), chemical (inertness to most chemicals), biological (biocompatibility) and electronic (high electronic carrier mobility, large band gap and dielectric breakdown strength, negative electron affinity), with the simultaneous presence of so many extraordinary qualities often resulting in added value for a given application.We are presently at a turning point in the development of diamond physics and applications. While some achievements can be considered well established, on the other hand, new opportunities and challenges are facing the scientific community, particularly with regard to novel exciting deposition processes and techniques or new properties and applications in electronics. This Enrico Fermi Course on "The Physics of Diamond" is particularly focused on the new developments and prospects, which may well constitute a reference point for a new generation of scientists at what may possibly be the beginning of a new age in diamond. The course attracted several of the most distinguished experts in the field as lecturers and an audience of almost as distinguished students and observers from 19 countries. Participation and discussions were lively to the very last day, ranging from traditional diamond physics to new diamond physics, and from well-known applications to the new exciting opportunities.The material in this volume is organized in the following way: the first part (13 lectures) is essentially devoted to growth and structure, the second part to properties and applications, with a closing lecture exploring new exotic diamonds in the distant future. The earlier lectures extensively cover the many processes of plasma chemical vapour deposition, including advanced contributions in theoretical modelling of these processes. Novel deposition mechanisms are considered: low-temperature CVD and laser-activated processes, including the so-called QQC experiments. This first part closes with a discussion of amorphous phases. In the second part, particular emphasis is placed on electronic properties and applications. This includes an extensive discussion of doping and, in addition, the promising perspectives of diamond as an electron emitter. Its newly discovered remarkable electron affinity properties lead to a new dimension in research and development, of great strategical importance for an increasing role of diamond in electronics.

Author: A. J. Neves
Publisher: IET
ISBN: 9780852967850
Category : Science
Languages : en
Pages : 454

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Book Description
Recent breakthroughs in the synthesis of diamond have led to increased availability at lower cost. This has spurred R&D into its characterization and application in machine tools, optical coatings, X-ray windows and light-emitting optoelectronic devices. This book draws together expertise from some 60 researchers in Europe and the USA working on bulk and thin film diamond. All fully refereed, the contributions are combined to form a highly structured volume with reviews, evaluations, tables and illustrative material, together with expert guidance to the literature.

Author: Christopher Nebel
Publisher: Elsevier
ISBN: 0080541046
Category : Science
Languages : en
Pages : 411

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Book Description
Part II reviews the state of the art of thin film diamond a very promising new semiconductor that may one day rival silicon as the material of choice for electronics. Diamond has the following important characteristics; it is resistant to radiation damage, chemically inert and biocompatible and it will become "the material" for bio-electronics, in-vivo applications, radiation detectors and high-frequency devices. Thin-Film Diamond II is the first book to summarize state of the art of CVD diamond in depth. It covers the most recent results regarding growth and structural properties, doping and defect characterization, hydrogen in and on diamond as well as surface properties in general, applications of diamond in electrochemistry, as detectors, and in surface acoustic wave devices * Accessible by both experts and non-experts in the field of semi-conductors research and technology, each chapter is written in a tutorial format· * Assisting engineers to manufacture devices with optimized electronic properties· * Truly international, this volume contains chapters written by recognized experts representing academic and industrial institutions from Europe, Japan and the US

Author: Kevin L. Jensen
Publisher: John Wiley & Sons
ISBN: 1119051762
Category : Science
Languages : en
Pages : 1305

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Book Description
A practical, in-depth description of the physics behind electron emission physics and its usage in science and technology Electron emission is both a fundamental phenomenon and an enabling component that lies at the very heart of modern science and technology. Written by a recognized authority in the field, with expertise in both electron emission physics and electron beam physics, An Introduction to Electron Emission provides an in-depth look at the physics behind thermal, field, photo, and secondary electron emission mechanisms, how that physics affects the beams that result through space charge and emittance growth, and explores the physics behind their utilization in an array of applications. The book addresses mathematical and numerical methods underlying electron emission, describing where the equations originated, how they are related, and how they may be correctly used to model actual sources for devices using electron beams. Writing for the beam physics and solid state communities, the author explores applications of electron emission methodology to solid state, statistical, and quantum mechanical ideas and concepts related to simulations of electron beams to condensed matter, solid state and fabrication communities. Provides an extensive description of the physics behind four electron emission mechanisms—field, photo, and secondary, and how that physics relates to factors such as space charge and emittance that affect electron beams. Introduces readers to mathematical and numerical methods, their origins, and how they may be correctly used to model actual sources for devices using electron beams Demonstrates applications of electron methodology as well as quantum mechanical concepts related to simulations of electron beams to solid state design and manufacture Designed to function as both a graduate-level text and a reference for research professionals Introduction to the Physics of Electron Emission is a valuable learning tool for postgraduates studying quantum mechanics, statistical mechanics, solid state physics, electron transport, and beam physics. It is also an indispensable resource for academic researchers and professionals who use electron sources, model electron emission, develop cathode technologies, or utilize electron beams.